Morphological traits of stem to indirect selection of resistance to lodging in Avena sativa L

The identification of traits associated with drought tolerance in popcorn is a contribution to support selection of superior plants under soil water deficit. The objective of this study was to choose morphological traits and the leaf greenness index, measured on different dates, to estimate grain yield (GY) and popping expansion (PE), evaluated in a set of 20 popcorn lines with different genealogies, estimated by multiple regression models. The variables were divided into three groups: morpho-agronomic traits—100-grain weight (GW), prolificacy (PR), tassel length (TL), number of tassel branches, anthesis-silking interval, leaf angle (FA) and leaf rolling (FB); variables related to the intensity of leaf greenness during the grain-filling period, at the leaf level, measured by a portable chlorophyll meter (SPAD) and at the canopy level, calculated as the normalized difference vegetation index (NDVI). The inbred lines were cultivated under two water conditions: well-watered (WW), maintained at field capacity, and water stress (WS), for which irrigation was stopped before male flowering. The traits GY (55%) and PE (28%) were most affected by water restriction. Among the morpho-agronomic traits, GW and PR were markedly reduced (>10%). Under dry conditions, the FA in relation to the plant stalk tended to be wider, the FB curvature greater and leaf senescence accelerated (>15% at 22 days after male flowering). The use of multiple regression for the selection of predictive traits proved to be a useful tool for the identification of groups of adequate traits to efficiently predict the economically most important features of popcorn (GY and PE). The SPAD index measured 17 days after male flowering proved useful to select indirectly for GY, while, among the morphological traits, TL stood out for the same purpose. Of all traits, PR was most strongly related with PE under WS, indicating its use in breeding programs. The exploitation of these traits by indirect selection is expected to induce increments in GY and PE.

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Correlation between honey production and some morphological traits in africanized honey bees (Apis melifera)

Ciência Rural ◽

10.1590/s0103-84782002000500020 ◽

2002 ◽

Vol 32 (5) ◽

pp. 869-872 ◽

Cited By ~ 3

Author(s):

Darcet Costa Souza ◽

Cosme Damião Cruz ◽

Lúcio Antônio de Oliveira Campos ◽

Adair José Regazzi

Keyword(s):

Honey Bees ◽

Morphological Traits ◽

Indirect Selection ◽

Pupal Weight ◽

Africanized Honey Bees ◽

Honey Production ◽

The Third ◽

Selection Of

This study focused on the correlation between honey production length and width of the tibia of the third pair of legs, corbicular area, pupal weight, and glossal length, in Africanized honey bees in Viçosa/MG, Brazil. Correlation values were relatively low, though always positive. The traits glossal length and pupal weight presented the lowest correlation to honey production: 0.225 and 0.410, respectively. The highest correlations were observed between length of the tibia and corbicular area and honey production: 0.587 and 0.549, respectively. In all cases, except pupal weight, correlation was significant. These findings support the notion that worker bees with larger corbicular areas may have a better ability to carry larger quantities of pollen to their hives, so that it is possible to improve honey production through indirect selection of this trait.

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Selection of resistance in western corn rootworm to Cry3Bb1, mCry3a, eCry3.1Ab, and Cry34/35Ab1 transgenic corn: Variations in traits in the laboratory and the field

10.1603/ice.2016.93324 ◽

2016 ◽

Author(s):

Bruce E. Hibbard

Keyword(s):

Western Corn Rootworm ◽

Corn Rootworm ◽

Transgenic Corn ◽

Selection Of ◽

Selection Of Resistance

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The Effects of Shock Vancomycin Concentrations on the Formation of Heteroresistance in Staphylococcus aureus

Antibiotics and Chemotherapy ◽

10.37489/0235-2990-2020-65-9-10-3-7 ◽

2020 ◽

Vol 65 (9-10) ◽

pp. 3-7

Author(s):

V. V. Gostev ◽

Yu. V. Sopova ◽

O. S. Kalinogorskaya ◽

M. E. Velizhanina ◽

I. V. Lazareva ◽

...

Keyword(s):

Staphylococcus Aureus ◽

In Vitro Selection ◽

Methicillin Resistant Staphylococcus Aureus ◽

High Concentration ◽

Short Term ◽

High Concentrations ◽

Selection Of ◽

Selection Of Resistance ◽

Test Cultures

Glycopeptides are the basis of the treatment of infections caused by MRSA (Methicillin-Resistant Staphylococcus aureus). Previously, it was demonstrated that antibiotic tolerant phenotypes are formed during selection of resistance under the influence of high concentrations of antibiotics. The present study uses a similar in vitro selection model with vancomycin. Clinical isolates of MRSA belonging to genetic lines ST8 and ST239, as well as the MSSA (ATCC29213) strain, were included in the experiment. Test isolates were incubated for five hours in a medium with a high concentration of vancomycin (50 μg/ml). Test cultures were grown on the medium without antibiotic for 18 hours after each exposure. A total of ten exposure cycles were performed. Vancomycin was characterized by bacteriostatic action; the proportion of surviving cells after exposure was 70–100%. After selection, there was a slight increase in the MIC to vancomycin (MIC 2 μg/ml), teicoplanin (MIC 1.5–3 μg/ml) and daptomycin (MIC 0.25–2 μg/ml). According to the results of PAP analysis, all strains showed an increase in the area under curve depending on the concentration of vancomycin after selection, while a heteroresistant phenotype (with PAP/AUC 0.9) was detected in three isolates. All isolates showed walK mutations (T188S, D235N, E261V, V380I, and G223D). Exposure to short-term shock concentrations of vancomycin promotes the formation of heteroresistance in both MRSA and MSSA. Formation of VISA phenotypes is possible during therapy with vancomycin.

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The dynamic of body and brain co-evolution

Adaptive Behavior ◽

10.1177/1059712321994685 ◽

2021 ◽

pp. 105971232199468

Author(s):

Paolo Pagliuca ◽

Stefano Nolfi

Keyword(s):

Morphological Traits ◽

The Body ◽

Morphological Variations ◽

And Control ◽

Selection Of

We introduce a method that permits to co-evolve the body and the control properties of robots. It can be used to adapt the morphological traits of robots with a hand-designed morphological bauplan or to evolve the morphological bauplan as well. Our results indicate that robots with co-adapted body and control traits outperform robots with fixed hand-designed morphologies. Interestingly, the advantage is not due to the selection of better morphologies but rather to the mutual scaffolding process that results from the possibility to co-adapt the morphological traits to the control traits and vice versa. Our results also demonstrate that morphological variations do not necessarily have destructive effects on robots’ skills.

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Selection of resistance againstVarroa jacobsoni across caste and sex in the honeybee (Apis mellifera L., Hymenoptera: Apidae)

Experimental and Applied Acarology ◽

10.1007/bf01218576 ◽

1992 ◽

Vol 16 (4) ◽

pp. 345-353 ◽

Cited By ~ 11

Author(s):

Robin F. A. Moritz ◽

Martina Jordan

Keyword(s):

Apis Mellifera ◽

Selection Of ◽

Selection Of Resistance

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Genetic Similarity of Avena sativa L. Varieties as an Example of a Narrow Genetic Pool of Contemporary Cereal Species

Plants ◽

10.3390/plants10071424 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1424

Author(s):

Magdalena Cieplak ◽

Sylwia Okoń ◽

Krystyna Werwińska

Keyword(s):

Genetic Diversity ◽

Avena Sativa ◽

Genetic Similarity ◽

Breeding Programs ◽

Central European ◽

Cereal Species ◽

Genetic Pool ◽

Selection Of ◽

High Genetic Similarity

The assessment of the genetic diversity of cultivated varieties is a very important element of breeding programs. This allows the determination of the level of genetic differentiation of cultivated varieties, their genetic distinctiveness, and is also of great importance in the selection of parental components for crossbreeding. The aim of the present study was to determine the level of genetic diversity of oat varieties currently grown in Central Europe based on two marker systems: ISSR and SCoT. The research conducted showed that both these types of markers were suitable for conducting analyses relating to the assessment of genetic diversity. The calculated coefficients showed that the analyzed cultivars were characterized by a high genetic similarity. However, the UPGMA and PCoA analyses clearly indicated the distinctiveness of the breeding programs conducted in Central European countries. The high genetic similarity of the analyzed forms allow us to conclude that it is necessary to expand the genetic pool of oat varieties. Numerous studies show that landraces may be the donor of genetic variation.

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Insecticide resistance status of Anopheles arabiensis in irrigated and non-irrigated areas in western Kenya

Parasites & Vectors ◽

10.1186/s13071-021-04833-z ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Pauline Winnie Orondo ◽

Steven G. Nyanjom ◽

Harrysone Atieli ◽

John Githure ◽

Benyl M. Ondeto ◽

...

Keyword(s):

Insecticide Resistance ◽

Vector Control ◽

Anopheles Arabiensis ◽

Crop Protection ◽

Indoor Residual Spraying ◽

Malaria Vectors ◽

Western Kenya ◽

Animal Protection ◽

Selection Of ◽

Selection Of Resistance

Abstract Background Malaria control in Kenya is based on case management and vector control using long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS). However, the development of insecticide resistance compromises the effectiveness of insecticide-based vector control programs. The use of pesticides for agricultural purposes has been implicated as one of the sources driving the selection of resistance. The current study was undertaken to assess the status and mechanism of insecticide resistance in malaria vectors in irrigated and non-irrigated areas with varying agrochemical use in western Kenya. Methods The study was carried out in 2018–2019 in Homa Bay County, western Kenya. The bioassay was performed on adults reared from larvae collected from irrigated and non-irrigated fields in order to assess the susceptibility of malaria vectors to different classes of insecticides following the standard WHO guidelines. Characterization of knockdown resistance (kdr) and acetylcholinesterase-inhibiting enzyme/angiotensin-converting enzyme (Ace-1) mutations within Anopheles gambiae s.l. species was performed using the polymerase chain reaction (PCR) method. To determine the agricultural and public health insecticide usage pattern, a questionnaire was administered to farmers, households, and veterinary officers in the study area. Results Anopheles arabiensis was the predominant species in the irrigated (100%, n = 154) area and the dominant species in the non-irrigated areas (97.5%, n = 162), the rest being An. gambiae sensu stricto. In 2018, Anopheles arabiensis in the irrigated region were susceptible to all insecticides tested, while in the non-irrigated region reduced mortality was observed (84%) against deltamethrin. In 2019, phenotypic mortality was decreased (97.8–84% to 83.3–78.2%). In contrast, high mortality from malathion (100%), DDT (98.98%), and piperonyl butoxide (PBO)-deltamethrin (100%) was observed. Molecular analysis of the vectors from the irrigated and non-irrigated areas revealed low levels of leucine-serine/phenylalanine substitution at position 1014 (L1014S/L1014F), with mutation frequencies of 1–16%, and low-frequency mutation in the Ace-1R gene (0.7%). In addition to very high coverage of LLINs impregnated with pyrethroids and IRS with organophosphate insecticides, pyrethroids were the predominant chemical class of pesticides used for crop and animal protection. Conclusion Anopheles arabiensis from irrigated areas showed increased phenotypic resistance, and the intensive use of pesticides for crop protection in this region may have contributed to the selection of resistance genes observed. The susceptibility of these malaria vectors to organophosphates and PBO synergists in pyrethroids offers a promising future for IRS and insecticide-treated net-based vector control interventions. These findings emphasize the need for integrated vector control strategies, with particular attention to agricultural practices to mitigate mosquito resistance to insecticides. Graphic abstract

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Genomic Prediction and Indirect Selection for Grain Yield in US Pacific Northwest Winter Wheat Using Spectral Reflectance Indices from High-Throughput Phenotyping

International Journal of Molecular Sciences ◽

10.3390/ijms21010165 ◽

2019 ◽

Vol 21 (1) ◽

pp. 165 ◽

Cited By ~ 3

Author(s):

Dennis N. Lozada ◽

Jayfred V. Godoy ◽

Brian P. Ward ◽

Arron H. Carter

Keyword(s):

Winter Wheat ◽

Pacific Northwest ◽

Prediction Accuracy ◽

Indirect Selection ◽

Yield Potential ◽

High Yield ◽

High Throughput Phenotyping ◽

Reflectance Indices ◽

Selection Of ◽

High Yield Potential

Secondary traits from high-throughput phenotyping could be used to select for complex target traits to accelerate plant breeding and increase genetic gains. This study aimed to evaluate the potential of using spectral reflectance indices (SRI) for indirect selection of winter-wheat lines with high yield potential and to assess the effects of including secondary traits on the prediction accuracy for yield. A total of five SRIs were measured in a diversity panel, and F5 and doubled haploid wheat breeding populations planted between 2015 and 2018 in Lind and Pullman, WA. The winter-wheat panels were genotyped with 11,089 genotyping-by-sequencing derived markers. Spectral traits showed moderate to high phenotypic and genetic correlations, indicating their potential for indirect selection of lines with high yield potential. Inclusion of correlated spectral traits in genomic prediction models resulted in significant (p < 0.001) improvement in prediction accuracy for yield. Relatedness between training and test populations and heritability were among the principal factors affecting accuracy. Our results demonstrate the potential of using spectral indices as proxy measurements for selecting lines with increased yield potential and for improving prediction accuracy to increase genetic gains for complex traits in US Pacific Northwest winter wheat.

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